This invention relates to a magnetic release system for electronic safety ski bindings, which acts as an interface between the electronic component and the physical release component of the binding.
For a skier's optimum safety and convenience, it is important that, while skiing, each ski boot is rigidly fixed with respect to the ski. On the other hand, in the event of an imminent fall it is important that the ski boot is disengaged from the ski to minimize possible injury to the skier. To achieve these goals, a wide variety of safety ski bindings have been developed for releasing a ski boot from a ski when the forces on the ski exceed a predetermined value.
Many ski bindings are entirely mechanical in nature. These mechanical bindings, while useful, tend to be somewhat unpredictable. Although the binding may be set to release when a predetermined force is applied, ice, snow, and dust may interfere with the binding's operation. Also, mechanical bindings often utilize mechanisms that latch the boot to the ski at the heel and toe of the boot, resulting in a binding that is most effective when force is applied at either the heel or the toe of the binding. This is adequate to achieve release when the skier falls either forward or backward, however, with twisting falls or with falls to the side, even though the total force may be sufficient to constitute a danger to the skier, the force on the heel or toe of the binding may be insufficient to achieve release of the ski boot from the ski.
In recent years, electronic ski bindings have been proposed to overcome some of these disadvantages. Some of these bindings include sensors that react not only to the forces acting on the toe and heel portions of the ski boot, but, additionally, the forces acting on the sides of the ski boot, such as occur with twisting falls or falls to the side. These sensors are designed to generate electrical signals when release is appropriate. Examples of such bindings are disclosed in U.S. Pat. No. 4,291,894 issued on Sept. 29, 1981 and incorporated herein by reference.
While these improved ski bindings utilize an electronic system for detecting forces on the ski, the physical release of the ski boot generally involves a mechanical system. Thus, it is necessary to design electronic bindings so that the electrical signals will result in actuation of the mechanical ski boot release. To achieve this goal, an interface between the electronic and mechanical components of the ski binding is necessary. The interface must be activated by the electronic signals and, in turn, actuate the mechanical release system that controls physical release of the ski boot from the ski. U.S. Pat. No. 4,130,296 issued on Dec. 19, 1978 and incorporated herein by reference discloses examples of such ski bindings. The solenoid utilized in that reference is an example of such an interface.
This invention concerns improved magnetic release systems that function as interfaces between the electronic and mechanical components of safety ski bindings. Magnetic release systems are proposed in earlier referenced U.S. Pat No. 4,291,894. According to that reference, a permanent magnet is fixed to a release arm with that unit moveably mounted to the ski binding. The release arm is retained in a latching position by a retainer spring. An electromagnet is fixably attached with respect to the ski binding. The poles of the electromagnet are aligned such that it is attracted to the permanent magnet when the electromagnet is not energized; that is, when the binding is in its latching position.
An electrical signal from the electronic component of the ski binding energizes the electromagnet. This results in pole reversal of the electromagnet and repulsion of the permanent magnet. The permanent magnet, with its attached release arm, then swivels against the force of the retainer spring to an unlatching position, thereby releasing the ski boot.
As discussed in greater detail below, a magnetic release system according to this invention provides several advantages over the above described system. It provides greater efficiency, and consequent lower energy consumption. Additionally, it is well suited for mass production and is designed to greatly reduce the possibility of faulty opening when a ski is jarred.